Proximal reamer

ABSTRACT

A kit includes an orthopaedic implant stem, and a reamer assembly for reaming a proximal portion of a cavity, said reamer assembly cooperating with a proximal portion of the orthopaedic implant stem, said reamer assembly comprising, a sleeve defining an inner periphery, said sleeve configured to fit over the proximal portion of the orthopaedic implant stem, said sleeve defining an outer periphery, and a reamer including a body defining a cavity formed therein for receiving at least a portion of the outer periphery of said sleeve, a plurality of cutting edges extending outwardly from said body, said cutting edges adapted for cooperation with bone, and a stem extending from an end of the body, wherein the sleeve comprises a locking feature and the stem comprises a connection feature to removably secure the sleeve to the proximal portion of the orthopaedic implant stem when assembled together.

This is a divisional application of application Ser. No. 11/529,799,filed Sep. 29, 2006, the entire contents of which are hereinincorporated by reference.

TECHNICAL FIELD OF THE INVENTION

The present invention relates generally to the field of orthopaedics,and more particularly, to an implant for use in arthroplasty.

BACKGROUND OF THE INVENTION

Patients who suffer from the pain and immobility caused byosteoarthritis and rheumatoid arthritis have an option of jointreplacement surgery. Joint replacement surgery is quite common andenables many individuals to function properly when it would not beotherwise possible to do so. Artificial joints are usually comprised ofmetal, ceramic and/or plastic components that are fixed to existingbone.

Such joint replacement surgery is otherwise known as joint arthroplasty.Joint arthroplasty is a well-known surgical procedure by which adiseased and/or damaged joint is replaced with a prosthetic joint. In atypical total joint arthroplasty, the ends or distal portions of thebones adjacent to the joint are resected or a portion of the distal partof the bone is removed and the artificial joint is secured thereto.

There are known to exist many designs and methods for manufacturingimplantable articles, such as bone prostheses. Such bone prosthesesinclude components of artificial joints such as elbows, hips, knees andshoulders.

Currently in total hip arthroplasty, a major critical concern is theinstability of the joint. Instability is associated with dislocation.Dislocation is particularly a problem in total hip arthroplasty.

Factors related to dislocation include surgical technique, implantdesign, implant positioning and patient related factors. In total hiparthroplasty, implant systems address this concern by offering a seriesof products with a range of lateral offsets, neck offsets, head offsetsand leg lengths. The combination of these four factors affects thelaxity of the soft tissue. By optimizing the biomechanics, the surgeoncan provide a patient a stable hip much more resistant to dislocation.

In order to accommodate the range of patient arthropathy metrics, a widerange of hip implant geometries are currently manufactured by DePuyOrthopaedics, Inc., the assignee of the current application, and byother companies. In particular, the S-ROM® total hip systems offered byDePuy Orthopaedics, Inc. include three offsets, three neck lengths, fourhead lengths and one leg length adjustment. The combination of all thesebiomechanic options is rather complex.

Anteversion of a total hip system is closely linked to the stability ofthe joint. Improper anteversion can lead to dislocation and patientdissatisfaction. Anteversion control is important in all hip stems.However, it is a more challenging issue with the advent of stems withadditional modularity.

The prior art has provided for some addressing of the anteversionproblem. For example, the current S-ROM® stems have laser markings onthe medial stem and the proximal sleeve. This marking enables thesurgeon to measure relative alignment between these components. Sincethe sleeve has infinite anteversion, it is not necessarily orientedrelative to a bony landmark that can be used to define anteversion. Infact, the current sleeves are sometimes oriented with the spout pointingdirectly laterally into the remaining available bone.

When a primary or index total joint arthroplasty fails, a revisionprocedure is performed in which the index devices (some or all) areremoved. Quite often the remaining bone is significantly compromisedcompared to a primary hip procedure. Significant bone loss is observed,often with a lack of bone landmarks typically used for alignment.

In a common step in the surgical procedure known as total hiparthroplasty, a trial or substitute stem is first implanted into thepatient. The trial is utilized to verify the selected size and shape ofthe implant in situ on the patient and the patient is subjected to whatis known as a trial reduction. This trial reduction represents movingthe joint, including the trial implant through selected typical motionsfor that joint. Current hip instruments provide a series of trials ofdifferent sizes to help the surgeon assess the fit and position of theimplant. Trials, which are also known as provisionals, allow the surgeonto perform a trial reduction to assess the suitability of the implantand the implant's stability prior to final implant selection. In orderto reduce inventory costs and complexity, many trialing systems aremodular. For example, in the Excel™ Instrument System, a product ofDePuy Orthopaedics, Inc., there is a series of broaches and a series ofneck trials that can be mixed and matched to represent the full range ofimplants. There is a single fixed relationship between a broach and aneck trial, because these trials represent a system of monolithic stemimplants.

Likewise, in the current S-ROM® instrument systems provided by DePuyOrthopaedics, Inc., there are neck trials, proximal body trials, distalstem trials, head trials and sleeve trials. By combining all of thesecomponents, the implant is represented. Since the S-ROM® stem is modularand includes a stem and a sleeve, the angular relationship or relativeanteversion between the neck and the sleeve is independent andrepresented by teeth mating between the neck and the proximal bodytrial. The proximal body trial has fixed transverse bolts that are keyedto the sleeve in the trialing for straight, primary stems. The long stemtrials do not have the transverse bolts and are thus not rotationallystable during trial reduction and therefore are not always used by thesurgeon.

With the introduction of additional implant modularity, the need forindependent positioning of the distal stem, proximal body and any sleevethat comprise the implants is required. Currently bowed, monolithicstems are offered with a fixed amount of anteversion, typically 15degrees.

Currently available implants, trials and instruments result in a lengthysurgical procedure. This lengthy surgical procedure includes the stepsof preparing the canal, removing the instruments to prepare the canal,implanting trials, performing a trial reduction and then implanting theprosthesis. This lengthy procedure increases the risk of the patient'ssurgical complications.

When utilizing currently available instruments, trials and surgicalprocedures, the surgeon must perform the trial reduction on the patientbefore the surgeon has any feedback regarding the appropriateness of thetrial and the positioning of the trial in the body. Adjustments in thepositioning and selection of the trial and resultant implants thusbecome difficult and time consuming to perform.

Utilizing the current instruments, the trials and implants all need tobe properly located and selected to obtain the optimum results for thepatient. The positioning of the trial with respect to the femur and theimplant with respect to the trial currently allow for much variationfrom procedure to procedure.

To optimize patient outcomes, orthopaedic surgery preferably conservesas much of the resected bone as possible. Current surgical proceduresrequire that sufficient bone be resected and removed by instruments inthe proximal bone to provide for clearance for the proximal trial andthe proximal implant. Thus, under current techniques, material must beremoved proximally on the bone to provide for the variety of positionsthat may be optimum for the patient.

US Patent Application Publication No. 20040122439 entitled “ADJUSTABLEBIOMECHANICAL TEMPLATING & RESECTION INSTRUMENT AND ASSOCIATED METHOD”,US Patent Application Publication No. 20040122437 entitled “ALIGNMENTDEVICE FOR MODULAR IMPLANTS AND METHOD” and US Patent ApplicationPublication No. 20040122440 entitled “INSTRUMENT AND ASSOCIATED METHODOF TRIALING FOR MODULAR HIP STEMS” are hereby incorporated in theirentireties by reference.

When performing hip arthroplasty using bowed stems, the distal canal isprepared with a reamer and the bowed step is installed in the reamedcavity. The longitudinal centerline of the proximal body of the implantis not in alignment with the centerline of the distal stem due to thefact that the distal stem is bowed. The reamer that prepares the distalcavity can not remove bone to provide clearance to the proximal body ina precise manner to minimize bone removal, due to the fact that theproximal body centerline of the implant is not in alignment with thedistal stem centerline. Either additional material must be removed bythe distal reamer from the proximal bone to allow for thisnon-alignment, or additional material must be removed by other means,for example by an osteotome. Either method requires additional boneremoval that is not clinically desired.

While the prior art has attempted to reduce the steps in surgicaltechniques and improve the ability to precisely remove bone to preparethe bone for receiving a proximal component, the need remains for asystem and apparatus to reduce the steps in surgical techniquesutilizing distal reamers and proximal bodies for modular implants.

The present invention is directed to alleviate at least some of theproblems with the prior art.

SUMMARY OF THE INVENTION

The design of the present invention gives the surgeon the ability toremove proximal bone after the distal implant has been implantedutilizing the fixed position of the implant to support a tool to removethe proximal bone.

The present invention provides a reamer that utilizes the distal implantin the long bone as a guide for proximally reaming the long bone.

After a long bone, for example a hip, has been resected, you must reamdistally to prepare canal for the distal stem implant in a modulardistal stem and proximal body implant assembly. This reaming is doneusing a tapered reamer. The distal stem implant has a 3° bend toaccommodate for the natural interior bow of the femoral canal in longdistal stem implant configurations used in revision arthroplasty.Because of the 3° bend, proximal reaming must be separately performed toremove the bone not removed by the distal tapered reamer. Once theimplant has been implanted, the surgeon may, utilizing the presentinvention, use the proximal end or tapered portion of the distal stemimplant as a pilot shaft for the proximal reamer. A protective sleevemay be placed over the tapered portion of the distal stem component ofthe implant to prevent damage to the distal stem component while theproximal reaming is being performed. The next step for the surgeon,after the proximal reaming, would be to proceed with implanting theproximal body implant or a proximal body trial. A trial reduction isthen performed and, if a trial reduction includes a proper implant/trialassembly selection, the corresponding implant is then inserted onto thedistal stem implant.

According to one embodiment of the present invention, there is provideda reamer for reaming a proximal portion of a cavity for use inimplanting a joint prosthesis. The reamer cooperates with a proximalportion of an orthopaedic implant stem. The reamer includes a bodydefining a cavity formed in the body for receiving at least a portion ofthe orthopaedic implant stem. The reamer also includes a plurality ofcutting edges extending outwardly from the body. The edges are adaptedfor cooperation with bone. The reamer also includes a stem extendingfrom an end of the body.

According to another embodiment of the present invention there isprovided a reamer assembly for reaming a cavity for use in implanting anorthopaedic implant stem of a joint prosthesis. The reamer cooperateswith a proximal portion of an orthopaedic implant stem. The reamerassembly includes a sleeve that fits over the proximal portion of theorthopaedic implant stem. The sleeve defines an outer periphery of thesleeve. The reamer assembly also includes a reamer having a bodydefining a cavity formed in the body for receiving at least a portion ofthe outer periphery of the sleeve. The reamer also has a plurality ofcutting edges extending outwardly from the body. The edges are adaptedfor cooperation with bone. The reamer also has a stem extending from anend of the body.

According to yet another embodiment of the present invention there isprovided a sleeve for use with an orthopaedic implant stem and aproximal reamer. The sleeve fits over the proximal portion of theorthopaedic implant stem. The sleeve defines an outer periphery of thesleeve.

According to a further embodiment of the present invention, there isprovided a kit for use in joint arthroplasty. The kit includes aproximal orthopaedic implant stem and a sleeve that fits over theproximal portion of the orthopaedic implant stem. The sleeve defines anouter periphery of the sleeve. The kit also includes a reamer. Thereamer has a body defining a cavity formed in the body for receiving atleast a portion of the orthopaedic implant stem. The reamer alsoincludes a plurality of cutting edges extending outwardly from the body.The edges are adapted for cooperation with bone. The reamer alsoincludes a stem extending from an end of the body.

According to a further embodiment of the present invention, there isprovided a method for providing joint arthroplasty. The method includesthe steps of resecting an end portion of a long bone and preparing acentral longitudinal opening in a medullary canal of the long bone. Themethod also includes the steps of providing a prosthetic stem componentand installing the prosthetic stem component into the opening in amedullary canal. The method also includes the steps of providing areamer including an opening for receiving the prosthetic stem componentand positioning the reamer onto prosthetic stem component with theopening of the reamer positioned at least partially over the prostheticstem component. The method also includes the steps of reaming a portionof the long bone with the reamer, removing the reamer; and installing aprosthetic body component onto the prosthetic stem component.

According to a further embodiment of the present invention, there isprovided a method for providing joint arthroplasty comprising. Themethod includes the steps of resecting an end portion of a long bone andpreparing a central longitudinal opening in a medullary canal of thelong bone. The method also includes the steps of providing a prostheticstem component and installing the prosthetic stem component into theopening in a medullary canal. The method also includes the steps ofinstalling a sleeve onto the prosthetic stem component and providing areamer including an opening for receiving the prosthetic stem component.The method also includes the steps of positioning the reamer onto thesleeve and reaming a portion of the long bone with the reamer. Themethod also includes the steps of removing the reamer and installing aprosthetic body component onto the prosthetic stem component.

The technical advantages of the present invention include the ability toreduce the number of steps in the surgical technique necessary toperform orthopedic surgery, for example hip implant surgery. Forexample, according to one aspect of the present invention a method forproviding joint arthroplasty is provided. The method includes the stepsof resecting an end portion of a long bone, preparing a centrallongitudinal opening in the canal, providing a prosthetic stemcomponent, and installing the stem component into the opening. Themethod also includes the step for providing a reamer for receiving theprosthetic stem component. The reamer is positioned at least partiallyover the prosthetic stem component. By placing the reamer over theprosthetic stem component a separate tool is not required to guide thereamer and a prosthetic trial or other component is not required to bepositioned in the canal to provide the support for the reamer. Thus thepresent invention provides for a reduction in the number of steps in thesurgical technique for joint arthroplasty.

The technical advantages of the present invention further include areduction in the number of instruments required to perform a jointarthroplasty, a reduced number of instruments in the instrument tray anda reduction in the related costs of the instruments. For example, andaccording to another aspect of the present invention, a method andapparatus for providing joint arthroplasty is provided in which thedistal stem implant is implanted into the reamed bone canal without theuse of a distal stem trial. Therefore, the instrument of a distal stemtrial is not required in this aspect of the present invention. Thus thepresent invention provides for a reduced number of instruments requiredto perform the joint arthroplasty.

The technical advantages of the present invention further include theability to remove bone proximally from the long bone after a distal stemimplant is installed into the long bone of the patient. For example,according to another aspect of the present invention a method forperforming joint arthroplasty is provided which includes providing aprosthetic stem component which is positioned in the canal of the longbone and providing a reamer for receiving the prosthetic stem component.A proximal reamer is positioned onto the prosthetic stem component andreams a proximal portion of the long bone. Thus the present inventionprovides for removing bone proximally after a distal stem implant isinstalled.

The technical advantages of the present invention further include theability to remove bone in a form that is eccentric with the center lineof the distal canal with a reamer. For example, according to anotheraspect of the present invention a reamer assembly is provided forreaming a proximal portion of a cavity for use in implanting a proximalbody implant of a modular joint prosthesis. The reamer cooperates with aproximal portion of the distal stem implant. The reamer assemblyincludes a proximal reamer and a sleeve that slips over the proximalportion of the distal stem implant. The sleeve may snap into a cavity ofthe proximal reamer. The orthopedic implant stem has a proximal portionthat is non-linear with the distal portion of the implant stem. Thus thepresent invention provides the ability to remove bone that is eccentricwith the distal canal with a reamer. Reaming of the proximal portion ofthe long bone may be better than broaching the proximal portion in thatbone may be too sclerotic or too weak and fragile to absorb theimpaction force from broaching.

The technical advantages of the present invention further include theability to use the implant as an implant shaft for reaming. For example,according to another aspect of the present invention a reamer assemblyfor reaming a proximal portion of a cavity for a joint prosthesis isprovided. The assembly includes a sleeve that fits over the orthopedicstem and a reamer that is fitted over the sleeve and is used to preparea proximal portion of the long bone. Thus the present invention providesfor ability to use the implant as a pilot shaft for the reamer.

The technical advantages of the present invention further include theability to perform in situa proximal body trialing on top of a distalimplant stem. For example, according to yet another aspect of thepresent invention a method providing joint arthroplasty is provided. Themethod includes the steps of resecting an end portion of the long bone,preparing an opening in the canal and providing a distal stem component.The distal stem component is installed into the canal and a reamer,including an opening for receiving the proximal portion of the distalstem component, is positioned over the stem with the reamer reaming insitua the proximal portion of the long bone for receiving the proximalbody component. A proximal body implant component or a proximal bodytrial component may be positioned over the prosthetic distal stemimplant component and a trial performed on top of the distal prostheticstem implant component. Thus, the present invention provides for theperforming in situa a proximal body trialing on top of a distal implantcomponent.

Other technical advantages of the present invention will be readilyapparent to one skilled in the art from the following figures,descriptions and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present invention and theadvantages thereof, reference is now made to the following descriptiontaken in connection with the accompanying drawings, in which:

FIG. 1 is a plan view of a reamer in position in a long bone forpreparing a bone canal for receiving a long bone prosthetic stem;

FIG. 2 is a plan view of a curved long bone distal stem implant inposition in the canal prepared by the reamer of FIG. 1 for use with thepresent invention;

FIG. 2A is a plan view of a straight long bone distal stem implant inposition in the canal prepared by the reamer of FIG. 1 for use with thepresent invention;

FIG. 3 is a plan view of a sleeve for use on the distal long bone stemof FIG. 2, according to an embodiment of the present invention;

FIG. 3A is a plan view of a sleeve with a cylindrical bore and acylindrical outer periphery according to another embodiment of thepresent invention;

FIG. 3B is a plan view of a sleeve with a cylindrical bore and a taperedouter periphery according to another embodiment of the presentinvention;

FIG. 3C is a partial plan view of a recess in the bore of a sleeve tomate with a protrusion on the distal long bone stem according to anotherembodiment of the present invention;

FIG. 3D is an end view of the sleeve of FIG. 3C showing the recess inthe bore of the sleeve;

FIG. 3E is an end view of a sleeve having three spaced apart recesses inthe bore of the sleeve according to another embodiment of the presentinvention;

FIG. 3F is a partial plan view of a protrusion in the bore of the sleeveto mate with a recess on the distal long bone stem according to anotherembodiment of the present invention;

FIG. 3G is an end view of the sleeve of FIG. 3F showing the protrusionin the bore of the sleeve;

FIG. 3H is an end view of a sleeve having three spaced apart protrusionsin the bore of the sleeve according to another embodiment of the presentinvention;

FIG. 3I is a plan view of a sleeve having a protrusion on the outerperiphery of the sleeve according to another embodiment of the presentinvention;

FIG. 3J is an end view of the sleeve of FIG. 3I showing the protrusionon the periphery of the sleeve;

FIG. 3K is an end view of a sleeve having three spaced apart protrusionson the periphery of the sleeve according to another embodiment of thepresent invention;

FIG. 3L is an end view of a sleeve having a rib or ring on the peripheryof the sleeve according to another embodiment of the present invention;

FIG. 3M is a plan view of a sleeve having a groove on the outerperiphery of the sleeve according to another embodiment of the presentinvention;

FIG. 3N is a plan view of a sleeve having a groove on the outerperiphery of the sleeve with a cylindrical bore and with a cylindricaloutside diameter according to another embodiment of the presentinvention;

FIG. 3P is a cross sectional view along the lines 3P-3P in the directionof the arrows;

FIG. 3Q is a plan view of the sleeve of FIG. 3N;

FIG. 4 is a plan view of the distal implant stem of FIG. 2 with thesleeve of FIG. 3M installed on the stem, to form a distal implant sleeveassembly;

FIG. 4A is a plan view of a distal implant stem with an externalprotrusion for use with the sleeve of FIG. 3C installed on the stem, toform a distal implant sleeve assembly according to another embodiment ofthe present invention;

FIG. 4B is an end view of the distal implant sleeve assembly of FIG. 4Ashowing the protrusion on the periphery of the distal implant stem;

FIG. 4C is an end view of a distal implant stem with 3 spaced apartexternal protrusions for use with the sleeve of FIG. 3E installed on thestem, to form a distal implant sleeve assembly according to anotherembodiment of the present invention;

FIG. 4D is a plan view of a distal implant stem with an external indentfor use with the sleeve of FIG. 3F installed on the stem, to form adistal implant sleeve assembly according to another embodiment of thepresent invention;

FIG. 4E is an end view of the distal implant sleeve assembly of FIG. 4Dshowing the protrusion on the external indent of the distal implantstem;

FIG. 4F is an end view of a distal implant stem with 3 spaced apartexternal indents for use with the sleeve of FIG. 3H installed on thestem, to form a distal implant sleeve assembly according to anotherembodiment of the present invention;

FIG. 4G is a top view of the implant/sleeve assembly of FIG. 4;

FIG. 4H is a plan view of a guide pin for use with the assembly of FIG.4 to protect the sleeve of FIG. 3;

FIG. 4I is a plan view of a implant/sleeve/pin assembly with the guidepin of FIG. 4H assembled onto the implant/sleeve assembly of FIG. 4;

FIG. 5 is a plan view of a reamer for use with a distal stem componentaccording to another embodiment of the present invention;

FIG. 5A is a plan view of a reamer for use with a distal stem componenthaving a cylindrical outer periphery, the reamer having a cylindricalopening an a cylindrical periphery according to another embodiment ofthe present invention;

FIG. 5B is a plan view of a reamer for use with a distal stem componenthaving a cylindrical outer periphery, the reamer having a cylindricalopening and a tapered periphery according to another embodiment of thepresent invention;

FIG. 6 is a plan view of the reamer of FIG. 5, partially in crosssection;

FIG. 6A is a plan view of the reamer of FIG. 5C, partially in crosssection;

FIG. 7 is a plan view, partially in cross section, of the reamer of FIG.5C shown in greater detail;

FIG. 7A is a partial plan view of FIG. 7 showing the spring loadeddetent positioned in the bore of the reamer to mate with a groove on theexternal periphery of the sleeve in greater detail;

FIG. 7B is a partial plan view of a proximal reamer showing a protrusionpositioned in the bore of the reamer to mate with a groove on the sleeveaccording to another embodiment of the present invention;

FIG. 7C is an end view of the proximal reamer of FIG. 7B showing theprotrusion positioned in the bore of the reamer;

FIG. 7D is an end view of a proximal reamer of FIG. 7B showing 3 spacedapart protrusions positioned in the bore of the reamer according toanother embodiment of the present invention;

FIG. 7E is a partial plan view of a proximal reamer showing a ringpositioned in the bore of the reamer to mate with a groove on the sleeveaccording to another embodiment of the present invention;

FIG. 7F is a partial plan view of a proximal reamer showing a groovepositioned in the bore of the reamer to mate with a protrusion on thesleeve according to another embodiment of the present invention;

FIG. 8 is a plan view partially in cross section of the reamer of FIG. 5in position on the distal implant/sleeve assembly of FIG. 4;

FIG. 9 is a partial plan view, partially in cross section, of the reamerof FIG. 5 with the sleeve of FIG. 3 in position on the reamer of FIG. 5to form a reamer/sleeve assembly according to another embodiment of thepresent invention;

FIG. 10 is a proximal body implant for use with the distal stem implantof FIG. 2;

FIG. 11 is a long bone implant assembly including the proximal bodyimplant of FIG. 10 in position on the long bone distal stem implant ofFIG. 2;

FIG. 12 is an enlarged partial plan view of the long bone implantassembly of FIG. 11 showing the tapered connection in greater detail;

FIG. 13 is an exploded view of the long bone implant assembly of FIG. 11including a head;

FIG. 14 is an assembled view of the long bone implant assembly of FIG.13; in position in the body;

FIG. 15 is a proximal trial component for use with the long bone distalstem implant of FIG. 2;

FIG. 16 is a kit for use in performing arthroplasty according to anotherembodiment of the present invention; and

FIG. 17 is a flow chart of a surgical procedure according to anotherembodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Embodiments of the present invention and the advantages thereof are bestunderstood by referring to the following descriptions and drawings,wherein like numerals are used for like and corresponding parts of thedrawings.

Referring now to FIG. 1 a long bone or femur 2 for use with the presentinvention is shown. The femur 2 includes an intermedullary canal 4 intowhich the prosthesis of the present invention may be inserted. The femur2 is resected along resection line 6 by, for example, a power tool, forexample, a saw. The resecting of the long bone or femur 2 exposes theintermedullary canal 4 of femur 2. A reamer 8 that may be a standardcommercially available reamer is positioned in the intermedullary canal4 of the long bone 2 to form cavity 10 for receiving an orthopedic jointimplant. The reamer 8 includes a plurality of longitudinally extendingflutes 12 which are used to remove bone and other biological matter fromthe intermedullary canal 4 to form the cavity 10. The reamer 8 may berotated by use of a connector 14 positioned on the reamer 8. Theconnector 14 may be any standard connector for example a Hudson or anA-O connector. The connector 14 is used to connect to a power tool 16for rotating the reamer 8. The power tool 16 may be any standard powertool. It should be appreciated that the reamer 8 may be rotated throughthe use of the connector 14 by a hand tool for example a “T” shapedhandle.

Referring now to FIG. 2, a distal implant stem 18 is shown fitted intothe cavity 10 formed in the intermedullary canal 4 of the long bone orfemur 2. The distal implant stem 18 may, as is shown in FIG. 2, be inthe form of a curved or bent stem. The natural femur has a curve thatmay best be replicated in an implant component, particularly when thedistal implant stem has a particularly long length, such as is used in arevision arthroplasty. The distal implant stem shape may be defined by aradius R extending from origin 21. The curved or bent portion of stem 18may be located mostly distally on the stem 18. The distal implant stemincludes an external tapered proximal portion 20 and a connector in theform of external threads 24 located proximally from the tapered proximalportion 20. The resection line 6 may generally correspond to theposition at which the stem 18, when implanted, begins the externaltapered portion 20 of the stem 18.

Referring now to FIG. 2A, it should be appreciated that the stem may bein the form of a straight or cylindrical stem 18A which does not includea curved or bent portion. The use of the proximal reamer in the presentinvention with such a cylindrical stem 18A may provide for bone removalfor receiving the proximal body that is precise and that minimizes boneremoval in comparison with other methods of removing bone for receivingthe proximal body.

According to the present invention, and referring now to FIG. 3, asleeve 24X for use with distal implant stems, for example stem 18 ofFIG. 2, is shown. The sleeve 24X is used with a proximal reamer 58C (SeeFIG. 5C). The sleeve 24X, as shown in FIG. 3, is fitable over thetapered proximal portion 20 of the distal implant stem 18. The sleeve24X defines an outer periphery 26X of the sleeve 24X. As shown in FIG.3, the sleeve 24X may be hollow and may include a cavity 28X extendinglongitudinally along sleeve center line 30X. The cavity 28X may definean inner periphery 32X of the sleeve 24X. The inner periphery 32X of thesleeve 24X may have any shape that mates with external periphery 19 ofthe tapered proximal portion 20 of the stem 18 (See FIG. 2).

Referring again to FIG. 2, the stem 18 includes the tapered proximalportion 20 as well as the threaded portion 22. Similarly, and referringto FIG. 3, the inner periphery 32X includes tapered portion 34X to matewith tapered portion 20 of the stem 18. Also, the inner periphery 32X ofthe sleeve 24X includes a threaded cylindrical portion 36X which mateswith internal threads 25 formed on the stem 18 (See FIG. 2).

The tapered portion 34X and the cylindrical portion 36X define a step orshoulder 38X positioned between the cylindrical portion 36X and thetapered portion 34X of the sleeve 24X. The sleeve 24X may include theouter periphery 26X having a shape compatible to that of the proximalreamer (See FIG. 5C). The outer periphery 26X may, as is shown in FIG.3, be tapered and defined by an included angle α. The included angle αmay be designed such that the sleeve 24X may have a wall thickness Twhich is generally uniform. Thus the tapered portion 34X of the internalperiphery 32X of the sleeve 24X may be defined by and include anincluded angle θ which is similar to the included angle α. As shown inFIG. 3, the internal angle α is slightly smaller than the included angleθ.

Preferably the sleeve 24X is fixedly secured to stem 18 of FIG. 2 sothat wear or damage does not occur to the tapered proximal portion 20 ofthe stem 18. Thus the sleeve 24X may include a feature for assuring thatthe stem 18 is fixedly secured to the sleeve 24X when assembledtogether. The angle αα of the internal periphery at the tapered portion34X may be designed such that it provides for a locking taper with thetapered portion 20 of the stem 18. Alternatively, the cylindricalportion 36X of the inner periphery 32X may include a feature of, forexample, internal threads 40X show in phantom, which may alternativelybe used to thread the sleeve 24X into engagement with external threads23 on the stem 18.

Referring now to FIG. 3A, an alternate embodiment of the presentinvention is shown as sleeve 24A. Sleeve 24A is like sleeve 24 of FIG. 3except that sleeve 24A includes an outer periphery 26A and an innerperiphery 32A that are both cylindrical. The sleeve 24A is suitable foruse with reamers having a cylindrical profiled driving surface.

Referring now to FIG. 3B, another embodiment of the present invention isshown as shown as sleeve 24B. The sleeve 24B is similar to the sleeve 24of FIG. 3 except that the sleeve 24B includes an outer periphery 26Bwhich is cylindrical and an inner periphery 32B which is tapered. Itshould be appreciated that the sleeve 24B of FIG. 3B may have a uniformconfiguration of the inner periphery 32B with no step or shoulder, aswell as, a simple cylindrical shape of outer periphery 26B.

The sleeve 24 may include an annular external ring or lip 42 whichextends outwardly from outer periphery 26 at lower end 44 of the sleeve24. The lip 42 may serve to prevent the outer periphery 26 of the sleeve24 to be permanently taper locked onto the proximal reamer.

While it is desirable to have the sleeve 24 be rigidly fixed to thedistal implant 18 when the proximal reamer is used with the sleeve 24,such rigid engagement of the sleeve 24 to the implant stem 18 may beacquired by an interference fit between the inner periphery 32 of thesleeve 24 and the tapered external portion 20 of the stem 18 if thecomponents are cylindrical or tapered locked if not.

It should also be appreciated that to assure the locking of the sleeve24 to the stem 18, the sleeve 24 may include a locking or securingfeature 46 that cooperates with a connection feature 56 on the stem 18to assure the rigidity of the sleeve 24 against the stem 18.

As shown in FIG. 3C, a sleeve 24C is shown which is similar to thesleeve 24 of FIG. 3 except that the sleeve 24C includes the sleeve/stemsecuring feature 46C in the form of an indentation. The indentation 46Cmay mate with a complimentary protrusion extending from the outerperiphery 26 of the external tapered portion 20 of the stem 18 (see FIG.2).

Referring now to FIG. 3D, the sleeve 24C may include a solitary indent46C as shown in FIG. 3D.

Referring now to FIG. 3E, another embodiment of the present invention isshown as sleeve 24E. Sleeve 24E is like sleeve 24C of FIGS. 3C and 3Dexcept that the sleeve 24E includes more than one indent, for example,three spaced apart indents 46E.

Referring now to FIGS. 3F and 3G, yet another embodiment of the presentinvention is shown as sleeve 24F. Sleeve 24F is similar to sleeve 24 ofFIG. 3 except that the sleeve 24F includes a sleeve/stem securingfeature in the form of a protrusion 46F extending inwardly from innerperiphery 32F of the sleeve 24F. As shown in FIG. 3G, the protrusion 46Fis a solitary protrusion. The protrusion 46F of FIGS. 3F and 3G may matewith an indent 56F formed on the external tapered portion 20F of thestem 18F of FIG. 4F.

Referring now to FIG. 3H, yet another embodiment of the presentinvention is shown as sleeve 24H. The sleeve 24H is like the sleeve 24Fexcept that the sleeve 24H includes three spaced apart protrusions 46H.

Referring now to FIG. 3I, yet another embodiment of the presentinvention is shown as sleeve 24I. The sleeve 24I is similar to sleeve 24of FIG. 3 except that the sleeve 24I includes a sleeve/proximal reamersecuring feature in the form of a protrusion 48I positioned nearshoulder 38I of the sleeve 24. The protrusion 48I extends outwardly fromouter periphery 26I of the sleeve 24I. The protrusion 48I serves to matewith an indent on the proximal reamer so that when the proximal reameris extracted from the stem 18, the sleeve 24I remains with the proximalreamer and does not need to be separately removed from the stem 18 (seeFIG. 2).

The protrusion 48I may have any suitable shape and may as shown in FIG.3I be tapered downwardly to make the engagement of the protrusion intothe opening easier in the downward direction of the reamer and to assurethat the sleeve 24 is removed with the proximal reamer. This featurereduces surgical procedure steps and saves time in the operating room.

Referring now to FIG. 3J, the protrusion 48I of the sleeve 24I may be asolitary protrusion.

Referring now to FIG. 3K, yet another embodiment of the presentinvention is shown as sleeve 24K. The sleeve 24K includes a protrusion48K extending outwardly from external periphery 26K of the sleeve 24K.It should be appreciated as shown in FIG. 3K that three separate spacedapart protrusions 48K may be utilized with complimentary indents formedin the proximal reamer (see FIG. 4).

Referring now to FIG. 3L, the protrusion 48I of the sleeve 24I may be asolitary protrusion that extends around the periphery of the sleeve toform a ring or lip.

Referring now to FIG. 3M, the sleeve 24X is shown in greater detail. Thesleeve 24X may include a sleeve reamer connection feature 48X in theform of an internal groove 48X extending inwardly from outer periphery26X of the sleeve 24X. The groove 48X may be positioned anywhere alonglongitudinal axis central line 30X of the sleeve 24X, but preferably islocated near the shoulder 38X of the sleeve 24X. The groove 48X servesto mate with a detent 88C formed in the proximal reamer 58C (See FIG.7A). It should be appreciated that the feature 48X should provide for anability to have relative rotation between the sleeve 24X and theproximal reamer 58C.

According to the present invention, and referring now to FIGS. 3N, 3Pand 3Q, a sleeve 24 for use with distal implant stems, for example stem18 of FIG. 2, is shown. The sleeve 24 is used with a proximal reamer 58(See FIG. 5). The sleeve 24, as shown in FIG. 3, is fitable over thetapered proximal portion 20 of the distal implant stem 18. The sleeve 24defines an outer periphery 26 of the sleeve 24. As shown in FIG. 3, thesleeve 24 may be hollow and may include a cavity 28 extendinglongitudinally along sleeve center line 30. The cavity 28 may define aninner periphery 32 of the sleeve 24. The inner periphery 32 of thesleeve 24 may have any shape that mates with external periphery 19 ofthe tapered proximal portion 20 of the stem 18. The inner periphery 19may be cylindrical and interferencely fit onto the tapered proximalportion 20 of the stem 18 of FIG. 2.

Referring again to FIG. 2, the stem 18 includes the tapered proximalportion 20 as well as the threaded portion 22. Similarly, and referringto FIGS. 3N, 3P and 3Q, the inner periphery 32 includes a distalcylindrical portion 34 to interferencely fit with tapered portion 20 ofthe stem 18. Also, the inner periphery 32 of the sleeve 24 includes aproximal cylindrical portion 36 with opposed double flats 37 which mateswith opposed double flats 27 formed on the stem 18 (See FIG. 2).

Referring again to FIGS. 3N, 3P and 3Q, the distal cylindrical portion34 and the proximal cylindrical portion 36 define a step or shoulder 38positioned between the cylindrical portion 36 and the distal cylindricalportion 34 of the sleeve 24. The sleeve 24 may include the outerperiphery 26 having a shape compatible to that of the proximal reamer(See FIG. 5). If the angle of the proximal reamer bore is small enough,the outer periphery 26 of the sleeve 24 may be cylindrical. The outerperiphery 26 may, as is shown in FIG. 3, be cylindrical and defined bydiameter DOS. The sleeve 24 may have a wall thickness T which isgenerally uniform. Thus distal cylindrical portion 34 of the internalperiphery 32 of the sleeve 24 may be defined by wall thickness T.

Preferably the sleeve 24 is fixedly secured to stem 18 so that wear ordamage does not occur to the tapered proximal portion 20 of the stem 18.Thus the sleeve 24 may include a feature for assuring that the stem 18is fixedly secured to the sleeve 24 when assembled together. The distalcylindrical portion 34 of the internal periphery 32 of the sleeve 24 maybe designed such that it provides for an interference fit with thetapered portion 20 of the stem 18. Alternatively, the cylindricalportion 36 of the inner periphery 32 may include a feature of, forexample, internal threads (not shown), which may alternatively be usedto thread the sleeve 24 into engagement with external threads 23 on thestem 18.

It should be appreciated that to assure the interference fit between thedistal cylindrical portion 34 of the sleeve 24 and the tapered portion20 of the stem 18 of the reamer 8, the sleeve may optionally havelongitudinal slots (not shown) through the wall of the sleeve 24. Theslot may be a single slot or a plurality of spaced apart slots. Theslots may partially extend along the length of the sleeve 24 or mayextend the fill length, splitting the sleeve 24. The slots permitadditional interference fit.

According to the present invention and referring now to FIG. 4, animplant sleeve assembly 50 is shown. The implant sleeve assembly 50includes the sleeve 24 of FIG. 3 positioned on the orthopedic implantstem 18 of FIG. 2. The orthopedic implant stem 18 is positioned in canal4 of cavity 10 of soft or cancellous bone in the canal 4 of the femur 2.The sleeve 24 may be loaded onto the orthopedic implant stem 18 in thedirection of arrow 52. The orthopedic implant stem 18 may be moved fromloading position 54 as shown in phantom to the installed position 56 asshown in solid.

While the sleeve 24 may be installed in situa on the orthopedic implantstem 18 already installed into the canal 4 of the cavity 10 of the femur2, it should be appreciated that the sleeve 24 may be preinstalled ontothe orthopedic implant stem 18 prior to the performing of the surgerysuch that the sleeve 24 may protect external periphery 19 of the stemtapered portion 20 of the stem 18 during shipment and during theinstallation of the stem 18 into the cavity 10 of the canal 4 of thefemur 2.

The sleeve 24 is preferably rigidly fitted against the orthopedicimplant stem 18. The rigid connection of the sleeve 24 to the stem 18may be accomplished by the fitting of the sleeve internal periphery 32of the sleeve 24 against the external periphery 19 of the stem taperedportion 20 of the stem 18. The internal periphery 32 of the sleeve 24may be cylindrical and may thus interferencely fit with the externalperiphery 19 of the stem tapered portion 20 of the orthopedic implantstem 18 defined by included angle θθ.

The orthopedic implant stem 18, like the sleeve 24, may include featuresto assure the rigid securement of the sleeve 24 to the stem 18. Forexample, and as shown in FIG. 4, the stem 18 may include a stem/sleeveconnection feature 56 for cooperation with the sleeve/stem connectionfeature 48 of the sleeve 24 (See FIG. 3).

Referring now to FIGS. 4A and 4B, yet another embodiment of the presentinvention is shown as implant sleeve assembly 50A. The implant sleeveassembly 50A is similar to the implant sleeve assembly 50 of FIG. 4,except that the implant sleeve assembly 50A includes a stem 18A whichhas a stem/sleeve connection feature in the form of a protrusion 56Aextending from the stem 18A. The protrusion 56A fits into the singleindentation 46C formed in the sleeve 24C of FIGS. 3C and 3D.

Referring now to FIG. 4C, yet another embodiment of the presentinvention is shown as implant/sleeve assembly 50C. The implant sleeveassembly 50C is similar to the implant/sleeve assembly 50A of FIGS. 4Aand 4B except that stem 18 of the implant sleeve assembly 50C includes aplurality of spaced apart protrusions 56C extending from stem 18C. Theprotrusions 56C cooperate with a plurality of indents 46E formed onsleeve 24E.

Referring now to FIGS. 4D and 4E, yet another embodiment of the presentinvention is shown as implant sleeve assembly 50D. The implant sleeveassembly 50D includes a solitary indent 56D formed on the stem 18D. Theindent 56D on the stem 18D cooperates with a solitary protrusion 46Fformed on sleeve 24F of FIGS. 3F and 3G.

Referring now to FIG. 4F, yet another embodiment of the presentinvention is shown as implant sleeve assembly 50F. The implant sleeveassembly 50F is similar to the implant sleeve assembly 50D of FIGS. 4Eand 4D. The implant sleeve assembly 50F includes a stem 18F whichincludes three spaced apart indentations 56F. The indentations 56F ofthe stem 18F cooperate with three spaced apart protrusions 46H formed onsleeve 24H of FIG. 3H.

Referring now to FIG. 4G the sleeve 24 is shown in cooperation with thestem 18 of the distal reamer 8. The stem 18 of the distal reamer 8includes opposed double flats 27 formed on stem 18. The proximalcylindrical portion 36 of the sleeve 24 includes opposed double flats 37formed in the proximal cylindrical portion 36 of the sleeve 24. Theopposed double flats 37 formed in the proximal cylindrical portion 36 ofthe sleeve 24 mate with the opposed double flats 27 formed on stem 18.The stem 18 of the distal reamer 8 also includes an elongated centralrecess 29 extending from end 31 of the stem 18 of the distal reamer 8.

Referring now to FIG. 4H a guide pin 33 for use with the implant sleeveassembly 50 of FIG. 4 to protect the sleeve 18 of FIGS. 3N, 3P and 3Q.The guide pin 33 fits onto the external threads 23 on the stem 18 ofdistal reamer 8 of FIG. 1. The guide pin 33 includes internal threads 35for mating with the external threads 23 on the stem 18 of distal reamer8. The guide pin 33 may have any shape for fitting into the proximalreamer 58 of FIG. 5. For example the guide pin 33 may have a generallycylindrical shape define by diameter DGP. The guide pin 33 may have arounded or bullet nose 43 to assist in guiding the reamer 58 onto theguide pin 33. The guide pin may include a through transverse opening-51for use in extracting the guide pin 33.

Referring now to FIG. 4I the guide pin 33 of FIG. 4H is shown assembledonto the implant/sleeve assembly 50 of FIG. 4 to form animplant/sleeve/pin assembly 45. The proximal reamer 58 of FIG. 5 isguided onto the implant/sleeve/pin assembly 45.

Referring now to FIG. 5, yet another embodiment of the present inventionis shown as reamer 58. The reamer 58 is utilized for reaming a proximalportion 62 of the cavity 10 formed in the canal 4 of the femur 2. Thereamer 58 is for use in implanting a joint prosthesis 62. The jointprosthesis 62 includes the distal stem portion 18. The reamer 58includes a body 66 defining a cavity 68 formed in the body 66. Thecavity 68 is adapted to receive at least a portion of the orthopedicimplant component, for example, stem 18.

The reamer 58 also includes a plurality of cutting edges 70 extendingoutwardly from the body 66. The edges 70 are adapted for cooperationwith bone, for example, the femur 2. The reamer 58 further includes astem 72 extending from an end 74 of the body 66. The body 66 may haveany suitable shape and may for example, be cylindrical, have a polygoncross-section, or have a periphery 76 that is tapered. The stem 72 mayhave any suitable shape and may include a connector 78 in the form of,for example, a standard commercially available connector, for example, aAO connector or an Hudson connector, capable of receiving a tool, forexample, a driver 80 for rotating the reamer 58 in the direction ofarrow 82. The reamer 58 includes cutting edges 70 that engage and removebone.

The reamer 58 may have any suitable shape and may have any number ofcutting edges 70. For example, there may be two, three, four, five,seven or more flutes. Preferably, the flutes are equally spaced andextend longitudinally along longitudinal center line 84 of the proximalreamer 58. The flutes 70 may run longitudinally with the longitudinalaxis 84 or may as is shown in FIG. 5 be helical or form an angle, forexample angle ββ with respect to the horizontal.

The cavity 68 formed in the proximal reamer 58 may have any suitableshape and may for example be cylindrical or have an external periphery86 which defines a cone. The internal periphery 86 of the proximalreamer 58 defines the cavity 68 and, preferably, has a shape that mateswith the proximal portion 20 of the stem 18.

As shown in FIG. 5, external periphery 71 of reamer 58 is defined bycutting edges 70 and may be tapered. The internal periphery 86 formed bythe cavity 68 may also be tapered. It should be appreciated that othershapes of these components maybe within the scope of the invention. Thereamer 58 includes a proximal internal cavity 39 for receiving the guidepin 33 of FIG. 4H. The proximal internal cavity 39 defines an end 41 ofthe internal cavity that provides a stop for cooperation with the bulletnose 43 of the guide pin 33. The reamer 58 may also include longitudinalslots 47 extending from the outer periphery 49 of the reamer to theproximal internal cavity 39 for viewing the insertion of the guide pin33 into the reamer 58 and to ease cleaning of the reamer 58. The reamer58 may have a solitary or multiple (for example 3 equally spaced apart)slots 47.

Referring now to FIG. 5A, another embodiment of the present invention isshown as proximal reamer 58A. Proximal reamer 58A is similar to theproximal reamer 58 of FIG. 5 except that the proximal reamer 58Aincludes cutting edges 70A that form an external periphery 71A that iscylindrical. Also, cavity 68A forms an internal periphery 86A which is,likewise, cylindrical.

Referring now to FIG. 5B, yet another embodiment of the presentinvention is shown as reamer 58B. The reamer 58B is similar to thereamer 58 of FIG. 5 except that the reamer 58B includes a cavity 68Bwhich forms an interior periphery 86B which is cylindrical. Cuttingedges 70B form an external periphery 71B which is tapered or conical.The external periphery 71B is defined by included angle αα.

Referring now to FIG. 5C, yet another embodiment of the presentinvention is shown as reamer 58C. The reamer 58C is utilized for reaminga proximal portion 62C of the cavity 10 formed in the canal 4 of thefemur 2. The reamer 58C is for use in implanting a joint prosthesis 62.The joint prosthesis 62 includes the distal stem portion 18. The reamer58C includes a body 66C defining a cavity 68C formed in the body 66C.The cavity 68C is adapted to receive at least a portion of theorthopedic implant component, for example, stem 18.

The reamer 58C also includes a plurality of cutting edges 70C extendingoutwardly from the body 66C. The edges 70C are adapted for cooperationwith bone, for example, the femur 2. The reamer 58C further includes astem 72C extending from an end 74C of the body 66C. The body 66C mayhave any suitable shape and may for example, be cylindrical, have apolygon cross-section, or have a periphery 76C that is tapered. The stem72C may have any suitable shape and may include a connector 78C in theform of, for example, a standard commercially available connector, forexample, a AO connector or an Hudson connector, capable of receiving atool, for example, a driver 80C for rotating the reamer 58C in thedirection of arrow 82C. The reamer 58C includes cutting edges 70C thatengage and remove bone.

The reamer 58C may have any suitable shape and may have any number ofcutting edges 70C. For example, there may be two, three, four, five,seven or more flutes. Preferably, the flutes are equally spaced andextend longitudinally along longitudinal center line 84C of the proximalreamer 58C. The flutes 70C may run longitudinally with the longitudinalaxis 84C or may as is shown in FIG. 5C be helical or form an angle, forexample angle ββ. with respect to the horizontal.

The cavity 68C formed in the proximal reamer 58C may have any suitableshape and may for example be cylindrical or have an external periphery86C which defines a cone. The internal periphery 86C of the proximalreamer 58C defines the distal cavity 68 and, preferably, has a shapethat mates with the proximal portion 20 of the stem 18.

As shown in FIG. 5C, external periphery 71C of reamer 58C is defined bycutting edges 70C and may be tapered. The internal periphery 86C formedby the cavity 68C may also be tapered. It should be appreciated thatother shapes of these components maybe within the scope of theinvention.

Referring now to FIG. 6, the cutting edge 70 of the reamer 58 may haveany suitable form. For example, the cutting edge 70 may include aplurality of spaced apart flutes 73. Each of the flutes 73 may as shownin FIG. 6 include a grouping of spaced apart reliefs 75. The reliefs maybe positioned on each of the flutes 73 and may form circular rings or asshown in FIG. 6 be spirally positioned around the reamer externalperiphery 71.

The reamer 58 may include an attachment feature 88 for cooperation withthe sleeve 24 such that the sleeve 24 is removed with the reamer 58 whenthe reamer has completed preparing the cavity for the proximal body. Theattachment feature 88 may have any suitable size and shape to assist inhaving the sleeve 24 be removed with the reamer 58.

Referring now to FIG. 6A, the cutting edge 70C of the reamer 58C mayhave any suitable form. For example, the cutting edge 70C may include aplurality of spaced apart flutes 73C. Each of the flutes 73C may asshown in FIG. 6C include a grouping of spaced apart reliefs 75C. Thereliefs may be positioned on each of the flutes 73C and may formcircular rings or as shown in FIG. 6C be spirally positioned around thereamer external periphery 71C.

The reamer 58C may include an attachment feature 88C for cooperationwith the sleeve 24X of FIG. 3 such that the sleeve 24X is removed withthe reamer 58C when the reamer has completed preparing the cavity forthe proximal body. The attachment feature 88C may have any suitable sizeand shape to assist in having the sleeve 24X be removed with the reamer58C.

Referring now to FIG. 7, the attachment feature 88C is shown in greaterdetail. The attachment feature 88 may be in the form of a protrusion oras shown in FIG. 7 be in the form of a spring loaded detent.

Referring now to FIG. 7A, the spring loaded detent 88C of the reamer 58Cis shown in greater detail. The spring loaded detent 88C includes a ball83C which is spring biased in the direction of the cavity 68C. Thespring 85C and detent 88C are positioned in an opening 87C. The detent88C receives the sleeve 24C by compressing the spring 85C and moving theball 83C inwardly. The spring 85C then extends to engage the groove 48Cin the sleeve 24C so that the sleeve 24C may be removed with the reamer58C.

The ball 83C of the detent 88C cooperates with groove 48C of the sleeve58C as shown in FIG. 3M. By providing the detent 88C to fit with agroove, for example groove 48M of FIG. 3M, the reamer 58C may rotatewhile the sleeve 24X is stationary or fixed to the distal stem 18.

Referring now to FIGS. 7B and 7C, yet another embodiment of the presentinvention is shown as reamer 58B. Reamer 58B is similar to the reamer 58of FIG. 7 except that the reamer 58B has a fixed solitary protrusion 88Bwhich extends inwardly from internal periphery 86B of the cavity 68B ofthe reamer 58B. The protrusion 88B of reamer 58B cooperates with groove48 of the sleeve 58, as shown in FIG. 3M.

According to the present invention and referring now to FIG. 7D, yetanother embodiment of the present invention is shown as reamer 58D. Thereamer 58D is similar to the reamer 58B of FIGS. 7B and 7C except thatthe reamer 58D includes three spaced apart protrusions 86D extendinginwardly from internal periphery 86D of the cavity 68D of the reamer58D. The protrusion 88D of reamer 58D cooperates with groove 48 of thesleeve 58, as shown in FIG. 3M.

The protrusion 88B of FIGS. 7B and 7C as well the protrusions 88D of thereamer 58D of FIG. 7D cooperate with a sleeve having a groove, forexample sleeve 24 having groove 48, as shown in FIG. 3M. The protrusionsand the groove cooperate such that the proximal reamer 58 may rotatewhile the stem 18 and the sleeve 24 are stationary.

Referring now to FIG. 7E, yet another embodiment of the presentinvention is shown as proximal reamer 58E. The proximal reamer 58E issimilar to the reamer 58D of FIG. 7D except that a continuous rib 88Eextends inwardly from internal periphery 86E of cavity 68E. The rib 88Ecooperates with groove 48 formed in sleeve 24 as shown in FIG. 3M.

Referring now to FIG. 7F, yet another embodiment of the presentinvention is shown as reamer 58F. The reamer 58F is similar to thereamer 58E as shown in FIG. 7E except that the reamer 58F includes acircumferential interior groove 88F extending outwardly from internalperiphery 86F formed in cavity 68F of the reamer 58F. The groove 88Fcooperates with, for example, the single protrusion 24A of FIG. 3K orthe rib 48K formed in sleeve 24K of FIG. 3K.

Referring now to FIG. 7G, the attachment feature 88 is shown in greaterdetail. The attachment feature 88 may be in the form of a protrusion oras shown in FIG. 7 be in the form of a spring loaded detent.

The spring loaded detent 88 includes a ball 83 which is spring biased inthe direction of the distal cavity 68. The spring 85 and detent 88 arepositioned in an opening 87. The detent 88 receives the sleeve 24 bycompressing the spring 85 and moving the ball 83 inwardly. The spring 85then extends to engage the groove 48 in the sleeve 24 so that the sleeve24 may be removed with the reamer 58.

The ball 83 of the detent 88 cooperates with groove 48 of the sleeve 58as shown in FIG. 3N. By providing the detent 88 to fit with a groove,for example groove 48 of FIG. 3N, the reamer 58 may rotate while thesleeve 24 is stationary or fixed to the distal stem 18.

Referring now to FIG. 8 and according to present invention, reamerassembly 90 is shown. Sleeve 24 and the guide pin 33 are is positionedin the proximal internal cavity 39 formed in the proximal reamer 58. Theorthopedic implant stem 18 is positioned in the cavity 68 of the reamer58 and the external periphery 19 of the proximal portion 20 of the stem18 mates with the inner periphery 32 of the sleeve 24. The sleeve outerperiphery 26 is rotatably engaged with internal periphery 86 of thereamer 58. The securing feature 48 of the sleeve 24 engages with theattachment feature 88 of the reamer 58. Similarly, the securing feature56 of the stem 18 connects with the locking feature 46 of the sleeve 24.

Referring now to FIG. 9, yet another embodiment of the present inventionis shown as reamer sleeve assembly 92. The reamer sleeve assembly 92includes the reamer 58 as well as the sleeve 24. As shown in FIG. 9, thereamer sleeve assembly includes a detent 88 formed on the reamer 58which cooperates with groove 48 formed in the sleeve 24. The outerperiphery 71 defined by the cutting edge 70 of the reamer 58 is utilizedto remove bone from proximal portion 89 of the femur 2. Cutting edges 70of the reamer 58 prepare cavity 91 in the proximal portion 89 of thefemur 2. The proximal cavity 91 is defined by angle ααα which isgenerally similar to the angle β defined by the external periphery 71 ofthe reamer 58.

Referring now to FIG. 9, it should be appreciated that the lip 42 of thesleeve 24 cooperates with the groove 48 formed in the sleeve 24 and theD-tent 88 to securably position the sleeve 24 in the reamer 58.

Referring now to FIG. 10, an orthopedic implant proximal component 90 isshown for use with the stem 18. The orthopedic implant proximalcomponent 90 includes a body 93 for receiving head 96 of the prosthesis.The body 93 defines a longitudinal opening 97 for receiving the stem 18.The body 93 further defines an external portion 98 which is sized to fitwithin the opening 91 prepared in the proximal portion 89 of the femur 2by the reamer 58 (See FIG. 9).

Referring now to FIG. 11, a hip stem assembly 99 to be used with thereamer and reamer assembly of the present invention is shown. The hipstem assembly 99 includes distal implant stem 18 to which proximal body93 is fixedly secured. The tapered portion 20 of the stem 18 is fittedinto longitudinal opening 97 formed in body 93 of the proximal component92. The tapered portion 20 of the stem 18 may include external threads21 formed on threaded portion 22 of the stem 18. A fastener in the formof a nut 100 may be used to assure the complete seating of the taperedportion 20 of the stem 18 into the longitudinal opening 97. The nut 100may be left on the orthopedic stem assembly 99 or may be removed oncethe stem 18 is securely fitted to the proximal component 92.

Referring now to FIG. 12, the proximal component 92 is shown in greaterdetail. As shown in FIG. 12, the proximal portion 20 of the distalcomponent 18 is shown fitted into longitudinal opening 97 of theproximal component 92. The threads 21 of the threaded portion 22 of thestem 18 engage the nut 100 and draw the stem into engagement with theproximal component 92. External periphery 98 of the proximal component92 is fitted into cavity 91 formed by the proximal reamer 58. The neck94 supports an externally tapered periphery 95 to which head 96 in theform of a spherical ball is securely fitted.

Referring now to FIG. 13, the components of the stem assembly 99 areshown in an exploded view. The stem 18, the proximal component 92, thehead 96, and the nut 100 are shown in their respective position prior toassembly. As shown in FIG. 13, the stem 18 has an arcuate shape. Thepresent invention is particularly well suited for use with orthopedicimplants with a curved or bent stem. It should be appreciated howeverthat the current invention may be used with straight or cylindrical orlinear stems as well. It should be appreciated that when using animplant with a curved or arcuate stem, a reamer can not be provided forpreparing simultaneously the distal cavity for the distal reamer and aclosely fitting reamed portion for the proximal body as these twocomponents do not have a common center line and thus can not be reamedsimultaneously.

Referring now to FIG. 14, orthopedic implant assembly in the form of ahip prosthesis 102 is shown. The hip prosthesis 102 includes the stemassembly 99 as well as head 96. A shell or cup 104 may be secured ontoacetabulum 106. The cup or shell 104 may mate directly with the head 96or a liner or bearing 108 may be positioned between the cup 104 and thehead 96. The orthopedic implant 102 may be made of any suitablematerial. The stem 99 may be made of any suitable durable material thatis compatible with the human anatomy and may for example be made of ametal. If made of a metal, the orthopedic implant components may be madeof, for example, cobalt chromium alloy, stainless steel alloy, or atitanium alloy. It should be appreciated that the liner or bearing 108may be made of a metal or may be made of a plastic, for example,polyethylene.

Referring now to FIG. 15, a trial neck 110 is shown for use with thedistal implant stem 18. The trial neck 110 substitutes for the proximalcomponent 92 and may be utilized to provide a trial reduction to assurethat the proper proximal component is used. A proximal implant similarto the trial neck 110 will be substituted once the trial reduction hasbeen performed and the proximal trial neck 110 is found to be suitable,thus making the corresponding proximal component suitable for thepatient.

Referring now to FIG. 16, a kit 112 for use in performing arthroplastyis provided. The kit 112 includes proximal reamer 58, as well as, sleeve24 and distal implant stem 18. The kit 112 may further include a distalreamer 8. The kit 112 may further include a proximal trial 110. The kit112 may further include proximal implant component 92. The kit 112 mayfurther include guide pin 33.

According to the present invention and referring now to FIG. 17, amethod 220 for performing arthroplasty is provided. The method 220includes a first step 222 of resecting an end portion of a long bone.The method 220 further includes a second step 224 of preparing a centrallongitudinal opening in a medullary canal of the long bone. The method220 further includes a third step 226 of providing a prosthetic stemcomponent and a fourth step 228 of installing the prosthetic stemcomponent into the opening in the medullary canal.

The method 220 further includes a fifth step 230 of providing a reamerincluding an opening for receiving the prosthetic stem component and asixth step 232 of positioning the reamer onto prosthetic stem componentwith the opening of the reamer positioned at least partially over theprosthetic stem component.

The method 220 further includes an seventh step 234 of reaming a portionof the long bone with the reamer and a ninth step 236 of removing thereamer. The method 220 further includes a ninth step 238 of installing aprosthetic body component onto the prosthetic stem component.

Although the present invention and its advantages have been described indetail, it should be understood that various changes, substitutions, andalterations can be made therein without departing from the spirit andscope of the present invention as defined by the appended claims.

We claim:
 1. A kit for use in joint arthoplasty comprising: anorthopaedic implant stem; and a reamer assembly for reaming a proximalportion of a cavity for implanting a proximal component of a jointprosthesis, said reamer assembly cooperating with a proximal portion ofthe orthopaedic implant stem, said reamer assembly comprising: a sleevedefining an inner periphery, said sleeve configured to fit over theproximal portion of the orthopaedic implant stem, said sleeve definingan outer periphery; and a reamer including a body defining a cavityformed therein for receiving at least a portion of the outer peripheryof said sleeve, a plurality of cutting edges extending outwardly fromsaid body, said cutting edges adapted for cooperation with bone, and astem extending from an end of the body, wherein the sleeve comprises alocking feature and the stem comprises a connection feature to removablysecure the sleeve to the proximal portion of the orthopaedic implantstem when assembled together.
 2. The kit of claim 1, wherein the innerperiphery of the sleeve has a tapered portion arranged to provide alocking taper when coupled to the stem.
 3. The kit of claim 1, whereinthe inner periphery of the sleeve incorporates internal threads arrangedto couple to external threads on the stem.
 4. The kit of claim 1,wherein the inner periphery of the sleeve is cylindrical and is arrangedto form an interference fit with the stem.
 5. The kit of claim 1,wherein the sleeve includes an annular external lip arranged to preventthe reamer forming a taper lock to the sleeve.
 6. The kit of claim 1,wherein: the sleeve is slidably fitted to the orthopaedic implantcomponent; and the body of the reamer includes a feature for securingthe sleeve thereto.
 7. The kit of claim 6, wherein said featurecomprises a cavity.
 8. The kit of claim 6, wherein said featurecomprises a protrusion.
 9. The kit of claim 1, wherein said plurality ofcutting edges are bounded by a frustoconical shape.
 10. The kit of claim1, wherein the cavity of said reamer body has a generally cylindricalshape.